The nose knows.

My last lover started smelling foul to me when I realized his drinking was problematic, that our relationship was toxic and that I would surely die by his hand if I continued down that path.

The yeasty bitterness of whiskey that I had once thought was novel was replaced by a deep and unyielding staleness. I no longer wanted to kiss him. And, despite the many warnings I had failed to heed before that point, it was only then that I finally decided things were not okay.

Two prominent researchers at the Monell Chemical Sense Center in Philadelphia have proven that women are able to sense emotions in other’s scents. Fear, anxiety, but definitely anger. Our biological responses are quite protective of us. Thank goodness for that.

But, this phenomena wasn’t something that just happened to me once. Friends, co-workers, even family members were just as vulnerable to my olfactory discomfort. Their smell changed or my experience of it changed and I found myself uninterested in intimacy, closeness, and even touch.

The body is an incredible machine. I never gave much thought to scent as part of the interpersonal relationship until I found myself repelled by just a whiff of the man I was supposed to love.

This is apparently not uncommon. Some researchers have called birth control pills to be “divorce pills” because of the way the drug changes the natural scent cycles of women. A landmark study published in 1995 established that women’s scent preferences were dependent on their hormonal status. Less than 10 years later, researchers Singh and Bronstad demonstrated that men rated women’s scents as more attractive and sexy during ovulation.

It is undeniable that certain scents create certain experiences, reactions or feelings in people. Lavender contributes to higher reports of pleasant moods and can increase respiration rates when combined with eucalyptus, but it has also been shown to decrease mathematical abilities. Many native cultures used herbs, not just in tinctures and tonics, but also for medicine — treating the mind, body and spirit.

According to author of the Scent of Desire, Rachel Herz, [scent] “was crucial to our ancestors’ existence and it remains so today, profoundly shaping our emotional, physical and even sexual lives”. And, yet we don’t often stop to smell our partners (or the roses) and even if we do, we are likely to be thrown off by modern hygiene — social scientists have postulated that we have become such a physical culture because it is the only way to truly snuff out the immunological, genetic and emotional compositions of our potential mate beyond the soaps and lotions and perfumes — or by our disconnection to our innate and biological drives.

So, what’s the takeaway here? I’d sum it up to say: you should probably do as the Toucan Sam instructs and “Follow your nose”.

Also, try going a few days fragrance free or spend your lunch hour meditating on what you smell. You might be surprised to find that you are often guided by this often unappreciated sense.